Place the stock, ginger, chilli and spring
onions in a large saucepan and bring to the
boil. Meanwhile, heat a griddle pan until
very hot and brush the steak with the oil.
Griddle the steak for 2 mins each side for
medium-rare. Transfer to a chopping board
and leave to rest for 1 min, then thinly slice.
Add the pak choi to the stock, then the
noodles, bring to the boil and simmer for
3 mins until tender. Ladle the stock, noodles
and pak choi into large serving bowls and
top with thin slices of steak.